Bradley Cooper's Limitless may be a worldwide box office hit but the Hangover 2 star couldn't manage to wrangle the lead of The Green Lantern from Ryan Reynolds during auditions.

"Ryan and I got to know each other through testing for Green Lantern," Cooper told TF exclusively. "They tried to separate everybody [who was auditioning]. They would usher you in one room and the other guy out the other room..."

"I was like, 'is this nuts?' I didn't allow that to happen. We were emailing each other. I know his wife very well from He’s Just Not That Into You. I love him. So now we’re always looking to do something together."

The new bromance will hopefully get its onscreen outing in an untitled police 'four-hander' set in San Francisco. In the meantime, Cooper got a first look at Reynolds in action.

"He’s put [the outfit] on for me a lot," he joked. "It’s great. He comes over and he hangs out in his Green Lantern uniform."

Reynolds admitted he would play an April Fool’s joke that he would be “The Flash.” He said he decided against it, because a comic book crowd wouldn’t appreciate the joke. So he was asked who should be The Flash. He answered, “Bradley Cooper.”